This invention relates to converters and more particularly to an oscillator circuit for operation as a converter of low DC input voltage to higher cyclic output voltages suitable of rectification or other loading circuits.
Traditional oscillator circuits known by such common names as Colpitts or Hartley, or the like, conventionally rely upon a gain element such as a vacuum tube or transistor and some external feedback scheme such as magnetically-coupled coils in input and output circuits to sustain oscillatory operation. Such circuits may oscillate at varying frequencies determined in part by tuned circuits to produce output signals at selected frequencies.
In accordance with the present invention, an oscillator circuit operates without specific tuning circuits using a gain element that provides internal coupling of current pulses between inductors in the input and output circuits, and avoids external coupling between such inductors. Current transfers through a collector-base junction of an NPN (or PNP) bipolar tranistor sustains oscillation to produce a level of output signal that is determined in part by the sizes of inductors used, and by loading in an output circuit connected across the gain element.